Several examples of a combined knife and fork have been known in the prior art U.S. Pat. No. 9,687 reissued May 3, 1881 to A. W. Cox discloses a Combined Knife and Fork providing a head portion having a flat upper surface and a convex lower lower surface. The surfaces intersect to define a sharp edge on the two outer tines. To increase the rigidity of the outer tines, which are stressed due to their use as a cutting blade, the bifurcations or slots between the outer tines and inner tines is less than the depth of the central bifurcation between the inner tines.
U.S. Pat. No. 1,294,031, issued Feb. 11, 1919 to Henry J. Bigelow, discloses a fork having a single outer tine having a sharpened or serrated edge
U.S. Pat. No. 4,771,541, issued Sep. 20, 1988, discloses a combination fork and knife having a serrated edge, a tab structure which allows a user to conveniently apply more pressure to the blade. The slot between the outer tine and the tine adjacent to it is not as deep, providing additional strength to the cutting edge.
In view of the above disclosures, there is still a need for an improved combined knife and fork having a more rigid cutting edge, reinforced tines and superior food handling abilities resulting from a fork head having an upper concave surface which also tends to result in a convenient cutting edge.